Postocene-Calderan Extinction (Future of The World)
The Postocene-Neocene '('P-No) extinction event, also known as the Seventh Extinction, or the Seventh Dying, is the extinction event of species between the Postocene and Neocene periods, around 32 million years in the future. It is considered the most severe extinction event since the Cretaceous-Paleogene extinction, with around 50% of known land vertebrate species going extinct. Causes There are a number of causes attributed to the Postocene-Neocene extinction, although most, if not all, are considered to be geological in some way. Around the same time as the extinction, the North American, Eurasian, African and Australian plates were moving towards each other, eventually culminating in the collision of their respective continents to form the base of the future supercontinent, Borealia. This lead to severe climate change, with mountain ranges being formed between Australia and Asia, as well as Africa and Europe. The mountains would block moisture from reaching the northern reaches of the continent, resulting in widespread desertification in the Northern Hemisphere. There is also the increasing levels of greenhouse gases, such as carbon dioxide, which lead to a steadily warming climate. leading to a greenhouse effect like that of the Holocene. With increasing temperatures, there is higher humidity and sea levels, but there is also more extreme weather patterns. What can be considered the most significant cause of the P-No extinction is extensive volcanic activity in central and northern Asia, which culminated in a flood basalt eruption in northern Mongolia. The eruption led to not only the destruction of local ecosystems, but also the expulsion of volcanic gases such as sulfur or methane, which further contributed to the global warming crisis. Organisms Lost in the Extinction Mammals Monotremes Monotremata - 30% Marsupials Didelphimorpha - 25% Paucituberculata - 10% Microbiotheria - 17% Dasyuromorphia - 30% Peramelemorphia - 20% Notoryctemorphia - 100% Diprotodontia - 35% Placentals Pliosa - 100% Cingulata - 100% Afrosoricida - 100% Macrocelidea - 21% Tubulidentata - 100% Hyracoidea - 12% Sirenia - 100% Eulipothyphla - 19% Chiroptera - 100% Artiodactyla - 100% Cetacea - 100% Perissodactyla - 100% Pholidota - 100% Carnivora - 83% Rodentia - 25% Lagomorpha - 31% Scandentia - 100% Primates - 100% Birds Paleognaths Rheiformes - 100% Tinamiformes - 100% Casuariiformes - 100% Apterygiformes - 100% Neognaths Galliformes - 40% Anseriformes - 85% Phoenicopteriformes - 60% Podicipediformes - 100% Columbiformes - 30% Mesitornithiformes - 55% Pteroclidiformes - 100% Apodiformes - 7% Caprimulgiformes - 6% Cuculiformes - 12% Otidiformes - 56% Musophagiformes - 65% Opisthocomiformes - 100% Gruiformes - 70% Charadriiformes - 49% Gaviiformes - 100% Procellariformes - 100% Sphenisciformes - 100% Ciconiiformes - 33% Suliformes - 100% Pelecaniformes - 100% Eurypygiformes - 100% Phaethontiformes - 100% Cathartiformes - 32% Accipitriformes - 100% Strigiformes - 12% Coliiformes - 100% Leptosomiformes - 100% Trogoniformes - 100% Bucerotiformes - 51% Coraciiformes - 98% Piciformes - 59% Cariamiformes - 100% Falconiformes - 45% Psittaciformes - 32% Passeriformes - 3% Aftermath and Effects Following the Neocene, and throughout the rest of the Basilozoic, the climate remained significantly warmer and more humid than it was during the Postocene, which had comparable temperatures to the present-day. The poles had significantly less ice while sea levels rose by 16-20 inches, levels higher than even during the age of man. There are now only three proper continents; South America, Antarctica, both of which are still rather isolated, and the new supercontinent of Borealia, which consists of North America, Africa, Australia and Eurasia. Around this time, Antarctica is also beginning to move north, towards the Equator, and is located near the Indian Ocean. This, along with the more tropical global climate, means that Antarctica has become significantly warmer than it ever could be today, with only the southern most areas having any large amounts of ice, while most of the northern continent is lush, temperate forest. Borealia is divided by a group of large mountain ranges; one spanning across the Africa-Europe boundary, over what was once the Mediterranean Sea, a smaller mountain range in the Middle East, another being between the Asian-Australian boundary, and one found across the center of North America. With the exception of the North American mountains, any land north of the mountain ranges are blocked from the perennial onset of moisture in the south, making most of Eurasia an arid steppe. In contrast, landmasses south of the mountain ranges, such as Africa and Australia, are completely exposed to the tropical onset of rain and warm currents, making a significant part of southern Borealia lush forest. Where there isn't rainforest, the land is usually a fertile savannah or flood plain. A perfect example of this is the African subcontinent; the Sahara Desert, which was once one of the most arid areas on Earth, is now a lush grassland teeming with life, while the Central African Congo extends twice as far down as it did throughout the Holocene and Postocene. Easily the most significant change between the Postocene and the Neocene is in the fauna. Until this point in time, mammals have remained the dominant organisms as they have since the Cenozoic. After the event, however, any mammal larger than a dog has gone extinct, such as ungulates, most Carnivorans, and Cetaceans. More adaptable, smaller groups such as rodents or lagomorphs survived, but mammals are no longer the dominant organisms on Earth. Birds have also suffered great casualties; by the Neocene, 18 orders have disappeared forever. Like mammals, more adaptable birds survived, but they are no longer the dominant aerial organisms. Until the later Neocene, Earth is caught in a struggle between groups of organisms for dominance, not unlike during the Triassic period following the Permian extinction. One major group in this struggle are the arthropods; having survived relatively unscathed, the higher oxygen levels and warmer climate means that arthropods can grow to gigantic sizes once more, like they did in the Carboniferous. In fact, the oxygen levels following the extinction became higher than they were in the Carboniferous, so arthropods can become even larger than during that time. Two other groups that survived were the amphibians and the reptiles. As both are classes of mostly ectothermic animals, they also diversified in the warmer climate; amphibians, for the first time in their history since the Paleozoic, diversified and positively thrived in their new environments, while reptiles were allowed to fill in the niches left behind by mammals. By the end of the Neocene, however, it was the reptiles that soon claimed the title of Earth's dominant organisms, with their adaptability being their prime advantage they have over other organisms, being more advanced than arthropods and amphibians, but also being less specialized than mammals and birds. By the Allocene, Earth was in a second Age of Reptiles.Category:Future of The World Category:Extinction Events